1. Field of the Invention
This invention relates to electrical connectors, and in particular to a modular jack.
2. Description of Related Art
Electrical connectors known as modular phone receptacles or jacks have been known for many years. Although connectors of this type were originally designed for use in telephone systems, they have found wide acceptance in a variety of other contexts. For example, modular jacks are now commonly used as input/output (I/O) interface connectors for enabling computers to communicate with each other and with a variety of peripheral equipment.
In order to receive a modular plug, the conventional modular jack is generally made up of a socket housing which includes a plug-receiving opening, opposed top and bottom surfaces joined by opposed side surfaces extending from the opening to a back surface, and a plurality of stamped, metallic elongated contacts mounted in the housing for engaging contacts of the corresponding plug. Each contact in this type of connector includes a contact mating portion at one end extending diagonally into the socket, a vertically extending lead portion at the other end, and a horizontally extending intermediate portion between the contact mating portion and the lead portion.
Because the above-described type of modular jack is often used for digital communications, the devices in which this type of connector is used have a tendency to emit high frequency radiation which can interfere with other electrical equipment. In addition, the devices are themselves vulnerable to noise or transients induced in an incoming line by external sources. While on-board filtering can often be used to solve such problems, the difficulty of designing circuitry which meets current emissions requirements as well as space considerations suggest that inclusion of filtering or transient suppression capabilities in the connector would be desirable under certain circumstances, and in particular where the cost of providing on-board filtering exceeds the cost of adding filters to the connector.
Nevertheless, while filtering has been used in a wide variety of different types of connectors, only a few attempts have been made to include such filters in modular jack connectors. These include the arrangement described in U.S. Pat. No. 4,726,638, which essentially provides a circuit board extending from the rear of the connector on which electrical components can be placed, and the arrangement described in U.S. Pat. No. 4,695,115 to Talend in which tombstone-style chip capacitors are soldered to the jack contacts and extend from the top of the connector to a shield placed over the contacts. These prior jack connectors have a number of disadvantages, including the fact that the filtering or transient suppression components extend too far outside the standard jack profile. In particular, considering that labor and assembly costs are often a high percentage of the cost of this type of connector, the above-described prior filtered jack connectors are disadvantageous in that they are difficult to assemble and cannot easily be customized to accommodate different filtering parameters in order to meet different customer requirements.